The Doctor is transmatted to Zeos where he is interrogated by the Shadow, who has brought the Tardis there and wants the Doctor's 5 segments to the Key To Time. The Shadow vanishes, returning to his bas where he then interrogates Astra. Romana & K-9 attempt to break in to the Transmat room but when they do Merak seizes the tracer and transmats ahead sealing the room behind him. Romana & K-9 follow, pursued by the Marshall's second in command Shapp who finds the Doctor on Zeos. The skull behind the mirror, a communication device from the Shadow, assures the Marshall there will be no more Zeon attacks so the Marshall decides to attack Zeos. Romana finds Merak, who has been led by the tracer to a bracelet belonging to Astra, The Doctor summons K-9 who helps them find Romana and then leads them to the Zeon commandant, the computer Mentalis who tell them the war is over and Obliteration is next. The Marshall nears Zeos and prepares to destroy it.

I remember nothing of the middle two episodes of this serial from my youth so it's always a big surprise to me when we find ourselves in the room containing Mentalis, complete with the UFO computer banks. And, writing this 2 days after having watched the episode, that's about all I remember of it now!

Playing Princess Astra of Atrios is Lalla Ward, the stage name of the honourable Sarah Ward, daughter of Edward Ward, 7th Viscount Bangor. Having studied at drama school from 1968-1971 she'd worked for a few television series.... but this role would prove to be a vital one for her getting her noticed and cast in the role for which she became famous for. More on this shortly..... I was convinced John Woodvine, here as the Marshal, had been in more than one Doctor Who but apparently not! But playing his pilot in the last few episodes of this serial is someone who's probably been in more episodes of Doctor Who than anyone else: regular supporting artist Pat Gorman!